This invention relates to spacecraft dispensers, and more particularly to a spacecraft dispenser for supporting a pair of spacecraft in a side-by-side configuration on a single dispenser shell.
Spacecraft dispensers are used to support spacecraft such as satellites on a launch vehicle such as a rocket during the launch phase of a mission in which the spacecrafts are deployed into orbit about the Earth. When two spacecrafts are to be deployed from a single launch vehicle, the most common dispenser approach for supporting these spacecrafts is known in the art as the xe2x80x9cDual Manifestxe2x80x9d approach. The Dual Manifest approach makes use of two separate conical payload adapters, each of which supports a single spacecraft. The adapters and their associated spacecraft are stacked vertically, and the upper adapter and spacecraft are supported by a cylindrical shell which encases the lower spacecraft. The cylindrical shell also serves to separate the lower spacecraft and its adapter from the upper spacecraft and its adapter.
The Dual Manifest approach described above has several significant drawbacks. For one, this approach is costly from a manufacturing standpoint because of the two independent adapters and two independent cylindrical support shells that are used to support each spacecraft, one above the other, on the launch vehicle. The two adapters and two support shells comprise a significant degree of weight. The upper support shell and its adapter also forms a very large piece of orbital debris when it is jettisoned prior to releasing the lower spacecraft. The added weight of the upper cylindrical support shell and adapter further serves to reduce the useable payload, thus further limiting the total weight of the two spacecrafts that can be carried by the launch vehicle.
Yet another approach to launching multiple spacecraft is the platform dispenser disclosed in U.S. Pat. No. 5,605,308, assigned to the assignee of the present application. The main drawback with this form of dispenser is the relatively high weight of the structure. This relatively high weight also limits the useable payload which can be carried into orbit by the launch vehicle.
It is therefore a principal object of the present invention to provide a dispenser structure which is capable of supporting a pair of spacecraft on a single dispenser shell to thereby provide a dispenser having a significantly reduced weight, as compared to previously designed dispensers.
It is a further object of the present invention to provide a dispenser for supporting a pair of spacecraft on a single dispenser shell in a side-by-side configuration, to thereby significantly reduce the weight associated with the dispenser.
It is yet another object of the present invention to provide a dispenser for supporting a pair of spacecraft thereon in a side-by-side configuration, wherein the dispenser includes a lower dispenser portion and a pair of upper support portions which extend from the lower portion, and which form a pair of support areas disposed within an envelope defined by an outer edge of the dispenser shell, for supporting a pair of spacecraft in a side-by-side configuration on the dispenser shell.
It is yet another object of the present invention to provide a dispenser which can be readily adapted to meet different, but standardized, spacecraft and launch vehicle mounting requirements.
The above and other objects are met by a twin lobe spacecraft dispenser apparatus and method in accordance with preferred embodiments of the present invention. The dispenser apparatus of the present invention includes a dispenser shell having a lower portion and a pair of upper support portions. In one preferred form the upper support portions are integrally formed with the lower portion and define two support areas at which a pair of spacecraft may be disposed on the single dispenser shell. In another alternative preferred embodiment a pair of cylindrical, upper dispenser rings are disposed on the upper support portions.
In various alternative preferred embodiments, the upper support portions comprise conical, integrally formed extensions of the lower portion of the dispenser shell which can support, directly thereon, a pair of spacecrafts. The two independent support portions enable a pair of spacecraft to be mounted on the dispenser shell in a side-by-side configuration, and also at a common elevation above the launch vehicle on which the dispenser shell is mounted.
In one preferred embodiment a pair of conical adapter shells are secured to the upper support portions of the dispenser shell to form extensions of the upper support portions. The conical adapter shells enable the upper support portions to interface with and support spacecraft utilizing a standard 37.0 inch (937 mm) mounting structure.
In another preferred embodiment the lower portion of the dispenser shell comprises a first portion and a second portion, with the first and second portions being secured together by an interface ring assembly. This enables the dispenser shell to be supported on launch vehicles having different diameter dispenser support surfaces.
The various preferred embodiments each include a one piece or a multi-piece dispenser shell which is adapted to support a pair of spacecraft thereon in side-by-side configuration, to thereby eliminate the need for the additional support structure that would otherwise be required when supporting a pair of spacecraft one on top of the other on a launch vehicle. This significantly reduces the weight of the dispenser apparatus and thus increases the useable payload capability of the dispenser, in addition to reducing the orbital debris created when the spacecrafts are deployed.